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XMLHttpRequestEventTarget.onloadstart

The XMLHttpRequestEventTarget.onloadstart is the function called when an XMLHttpRequest transaction starts transferring data.

Syntax

XMLHttpRequest.onloadstart = callback;

Values

  • callback is the function to be called when the transaction begins to transfer data.

Example

var xmlhttp = new XMLHttpRequest(),
  method = 'GET',
  url = 'https://developer.mozilla.org/';

xmlhttp.open(method, url, true);
xmlhttp.onloadstart = function () {
  console.log("Download underway);
};
xmlhttp.send();

Specifications

Specification Status Comment
XMLHttpRequest Living Standard WHATWG living standard

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1 (Yes) 1.0 (1.7 or earlier) 7 (Yes) 1.2
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? 1.0 (Yes) (Yes) ? ? ?

 

Document Tags and Contributors

 Contributors to this page: erikadoyle, teoli, rolfedh, Sheppy
 Last updated by: erikadoyle,